Then air flow through the outside core... to to get heat.. to the passengers.)

If the thermostat is bad, wrong
temperature rating , backwards (upside down), or the system is full of
air, there will be no hot water. No hot water?, means NO JOY
! The thermostat must be stamped, 189/192/195/200F Nothing lower ever.
On this page I will attempt to cover all Sidekicks and Trackers, 89 to
2004, and even new Grand Vitara's that use motor dampers.....

Given the blower works perfectly (if dead, check its fuse in the
cab fuse panel, get full blower fan flow. (if not, see dead fuse, or
bad switch or resistor block below)

The Engine coolant must attain (reach or exceed) and hold at 180F (see stamp on lip of thermostat actual) (hold not fluctuate) Newer cars are near 200F.

This hot coolant (50% Antifreeze) must pass through the
heater core in the dash. Both hoses get hot to touch 180F? is ouch
level hot to most folks, so, put hand on the hose, are both hot? (or the gun test)
No?, bad news, ever back flush it last service (2
year checks?)

Some cars (not this car) have a water valve on same hoses, just before the firewall, does moving the blue-red (cold/hot) lever in the dash, open and close this valve?, if not, the cable is broken, (or the nasty old vacuum servo's dead on other brand cars.).

Now that hot coolant passes though the cab core and hose,
we have a chance at cab heat. The Core dampers must be in the
heating position, with out the fresh air selected ,use recirculate
mode. (fresh air has no lower limits, so.... dont use fresh for testing heater)

On newer cars, they have 1 to 4 damper motors, that is, true
electric motors ,they can fail, and you will need a schematic or FSM to
trouble shoot them (or alldata.com). The FSM tests are unique to each car , make, and year.

In
fact, make sure all cables there, move there end piece cams , and moves
fully from end to end. (play with the controls, and watch the
cables end to end, to the all work and do their jobs.? So simple this
is, compared to motor drive dampers.

If the cable sheaths, are not clamped down,
the cables are rendered useless, clamp them now. They must now be
adjusted, if this was bad. (broken clamps) Adjust for full controls end to end.
Just like a bicycle brake lever. Use tie wraps to make your own clamps?

Now, air might flow through the core, some cars
(many)( leaves fall inside (pin needles?) down the cowl vent intake and
pack the heater core full of this trash, you will have to clean
it. THE
CORE PULL, SLIDE SHOW.

Keep in mind on the old
cars, you can at anytime move the dampers by hand, disconnected.
proving the door is opened, by HAND. This be first, before
pulling any heater casing, for sure.

Bingo,
you have heat.
(maybe, not to where you want it?, but you have heat how)
if not going to
the right place? then the mode cable is broken. (on newer cars,
the cable is now a silly motor seen below and complex tests)

The Damper evolution : (this history, shows how inportant the FSM is on cars with mode motors, they all work different)1989 to 1998 are 100 % cable systems (all modes and heat)
HVAC systems can have 1 motor or 3. Some are a mix of damper
motors and cables and vacuum servo's , some car makers call these,
Electric damper Acutators. A fancy name for a motor and cheap
plastc gears inside.
The bad news is each brand of motor works differently and eash have a very UNIQUE TEST, detailed in the FSM.
Damper motors:The first year, GV, 1999 to 2002 Grand Vitara, uses one single motor , same as the Vitara. See resistance test here. monster 4 mode control motor,Starting in 2003 the Grand Vitara, has the new 3 mode actuator motors and an electronic controller to make it all work.

Even my 2004 Chevy Tracker uses a full cable system and no water valve.
No damper motors here. GM uses different parts, oddly than any Vitara. (so make sure you are looking at the correct FSM)The 04 Vitara uses 2 cables and this motor (see test here).Get
your FSM , buy it and read the HVAC
sections for your
car.
FSM = Factory Service Manual, as sold at your
dealer or used at fleabay. (or Helm.com) Suzuki's are here, at pitstop.

Fan
dead. all speeds or 1 or 2 ? (see above 2 links) If high speed
works the fan is ok, only the switch and resistor block is bad. (mine
was both bad)

If
heat only works in circulation mode, then the fresh air vent is blocked at
ANY POINT. Leaves in cowl tank air plenum, rodent nests, etc. or
its flap is busted.

Lots of IF's:
If the fan runs at full speed and the cab heat is poor check for
weak heat ,at the 2 cab heater hoses between the Firewall and the
engine. (I use an IR gun ,and see 170F or more, my new 195F thermostat , even more....)

If the heater hose, is too cool, then the core in the heater is packed
up, or
the fittings/plumbing, feeding said tubes, are packed up. (assumes engine
coolant at thermostat housing is 180F or more.)

If the engine is fully hot, and those heater core 2 hoses are hot (
180F+) AND
the fan is running at full speed on high, cap is still frigid?, then the heater
flaps are jammed
closed. See all damper
flaps here.
The old Suzuki has no water valve (heat lever) it has a flap that blocks or
allows air to pass through the core , so the water flows through the
core 24/7 (always ) Flaps, doors, dampers all are same meaning.
Make sure the cables to the flaps (Suzuki calls them dampers) are
working, and the outer sheath is not flexing (moving). (only the inner
wire must move and the end ,of wire must move the damper arms)
If the fan is dead ( or one speed is dead) (heater fan in cab)
then check the heater
resistor block. Seen here.
Resistor Block?: Remove glove box door ,2 screws, see that
resistor ( it's air cooled) and a bad resistor ( they are a naked type)
will be blown to bits. (gone).

Now we are at the last point,
The core is hot, the engine is hot the flaps are open the
fan failing, (whole or in part ,fan fail).THE
CORE PULL, SLIDE SHOW.

Water flow: (a fully hot engine 180F+ degree's)
If you put your hand (for 1 second max) on to both heater core hoses, passing through the fire wall, and one is very cool,
that is a sign that you have a clogged core (or source feeds,
your are touching now, are clogged) (now is the time for a full cooling
back flush now , huh?)THE FAN SWITCH and speed
limiting resistor block. Step one, is to make sure that Fuse 12 is good. (12vdc on both sides key on)
We now have a bad fan switch.

My 97 Heater switch was warped bad. by the heat of the Sun.
Cooked it to DEATH and almost all Sidekicks this year , are failed or about to.
The side clips warped (pop) and can no longer
retrain the switch guts.
I fixed mine this way, because none of the tiny parts ,were missing inside. (1 ball and spring)
Tie warps solved this issues perfectly! FINDING a good switch , is near impossible (as I write)

In a nut shell: The switch ACCESS methods. 1996/97 (some 98s are more complex with buttons, so get
help from the 98 FSM)

Pull the battery minus lug.

Remove ash tray

Pull front bezel off HVAC center console surround , it just
pulls out. By the way, HVAC, is Heating
Ventilation and Air Conditioning.

Remove up to 4 slider knobs. (pull them)

Remove lamp pod , from bezel.

Remove the slider surround plate , 4 screws .

The slider mechanism and the switch are in clear view.

I can pull the control pod just enough back to un mount the
switch and its elect. plug.

In
96 , they dont have 2 switch screws, it snaps in. ( there are 2
systems !JAPAN
made and CAMI MADE heaters, they are different in there design)

Buying
the Suzuki switch ? are you? good luck there, I'm told that
the last year for buying just the switch is 1991. ( sadly) ( poor service? at Suzuki?, any wonder they chapter 11?) IMO ! now shutting down in Canada.

I
can clean my switch and file the contacts. Do not lose the tiny
steel ball and spring, or all hope is lost. Find a room
with no
rugs or floor drains and take it apart. << hint.

CAMI is Canada plant (shut down), Japan is the Iwata JAPAN plant
made. You VIN code tells you which MFG plant the car was made.
My
97 the switch had plastic snaps (Cami) no screws the plastic warped
from sun and sprung, so (after contact clean and lube) I
used tie wraps to secure it for 100 more years. LOLDo not remove switch internals in the car, go to a place you can find
the parts that fly out. 1 spring , contact and a tiny ball bearing
inside. Don't lose them.

The side of the switch , has the P/N and Suzuki says , can not be had.
(last digit 0 ,was missing on my connector P/N) By the way
P/N = part number......

Photo 1: Whole Switch out, internals, in place and a spare
to the right.
Below is 96/97 in 1998 pushbutton option was added.,
below has snap out switch. In 1996 the switch is part of total
assembly and not sold seperately. (not up to now). So will be
expensive. $120 or so. But ACdelco has one for $50 and so does, SMP SM404.

Mixing
switches between CAMI and JAPAN versions or years, is a problem... as is Generation changes..... (you won't
know what you have in the car until you look, carefully)
The switches vary by if A/C is present or not, year, and what factory PLANT made it.
The Suzuki switch is Discontinued. As is the total assembly seen below.
The GM is still sold. (GEO) 30007405 and 7399. My GEO parts book does not show all versions. of switches.
Photo 2: 1992 to 1995, Sidekick. SHOWS the switch as seperate, and
very hard to find. below is Japan, version 64ABO is
CAMI plant version (VIN prefix tells plant)
The drawing clearly
shows, JAPAN switch is missing. (did suzuki use wrong drawing here?) My guess is drawing is wrong.

The blower fan switch for 89-91 is 37870-60A01,
ID 29 below and is missing on
the 92-95 same pages, in the Suzuki parts book.
part 29 below mates to right side of part 37 above. If found, its
more like $38 part, unlike above.
The switch is still sold at Suzuki but not the whole assembly 37 above.

Rumor has it that the full 96/97 assembly will fit earlier years.
Amazon sells it, the one SMP switch assembly. for 92-97GEO Tracker , ACDelco 15-73369, and at $50 a great price.That motor resistor block is next topic:
The resistor block is bad if fan ONLY fails below HIGH, There are no RELAYS and the fan always runs on high , if the above switch is good.
Remove glove box door to reach the resistor block. The block is sold in almost all autostores, see my buy parts page here.Typical early wiring:
Most wiring looks like this. Typical of all 92 to 1995. see the other generations, here.
The blower must blow on high. If not , remove glove box door and
hot wire the fan, using a 12vdc battery with 15 amp inline fused jumper
wires. 16gauge wire.(per FSM hot wire rules) if it blows, good, the blower is good, (easy
, huh?)

If it don't blow hot wired, the blower blower is bad
If the blower is working on high but not other speeds the
resistor block is bad (99% of time) if not then the wires or
switch is bad, any voltmeter on earth can find this failure ,even
a $10 walfart meter.
A volt meter finds this failure easy, 12vdc to a dead blower pink
wire. is a dead motor.
If 12vdc does not reach, the blower motor,
then check at switch high pink pin? if this is dead (0v) then move
meter to lt-grn wire pin, of switch, if dead ? (0v), then the
fuse is blown or that wire is cut , check for 12vdc on both sides of
the fuse 12. if one side is dead, that be a blown fuse.
Fuses that look blown are.
Fuses that look good, can in FACT be bad.Here are the official
Suzuki part numbers: for the above RARE switch all prefixed with 74400-
1989 Iwata -60A10 (early year in japan made) not in stock .
1989.5 to 1991 CAMI -60A11 (Suzuki stocks these)
92-95 CAMI 64AB0
92-95 Iwata 64A11 (says with motor,
ouch) (SMP
clone HS404)
Amazon ?
96/97 Iwata 64A12
1998 Iwata 78E10 (stocked)
Buy them (stocked) at the 4 links shown here, called Dealers list.